.bg-video {
    position: absolute;
    top: 0;
    left: 0;
    z-index: -1;
    opacity: .25;
    height: 100%;
    width: 100%;
    overflow: hidden; //设置超出隐藏

    &__content { 
        height: 100%;
        width: 100%;
        object-fit: cover; //设置视频填充方式
    }

}